This contract is part of a collaborative effort to improve treatment planning with neutrons and with charged particles (protons, helium ions, pi-mesons, and heavy ions). In addition to developing optimal treatment plans for the treatment of tumors in various anatomic sites with the particle beam at its own institution, the collaborative working group is conducting a comparison of treatment plans for selected tumors in each anatomic site. Whenever possible, measurements in patients or phantoms will be made to check the accuracy of the treatment planning.